4, 4&#39;-dipyridyl diheterocyclic carbamyl methyl quaternary ammonium salts



United States Patent This invention related to new bipyridylium quaternary salts, to'processes for their preparation and to herbicidal compositions containing them.

U.K. specification No. 813,532 discloses the use as herbicides of compounds of" the formula:

where R and R are alkyl radicals of not more than four carbon atoms which are substituted with a carbamyl or N-substituted carbamyl group; and X- is an anion.

We have now found, according to the present invention, that certain N-substituted carbamyl compounds of the formula shown above show selective'herbicid-al activity against broad-leafed species compared with their activity against grass species. The selective compounds are those of the formula:

where R, and R are both hydrogen atoms, or are each an alkyl radical of 1-3 carbon atoms or an alkoxyalkyl of 2, 3 or 4 carbon atoms, or R and R together with the nitrogen atom to which they are attached constitute a pyrrolidine, piperidine or morpholine ring optionally having a methyl radical as substituent; and X- is an anion. The anion X- can be a monovalent ion, for example chloride,,iodide, or bromide, or a divalent ionwhere of course the symbol 2X. in the above structural formula represents a single ion rather than two monovalent ions. The choice of anion depends to'a large extent upon the solubility of the respective salts in water and upon the ease with which the salts can be prepared.

The invention also consists in a process for the preparation of the compounds of the invention, in which 4,4- bipyridyl or a mono-quaternary salt of the formula:

where R R and X- have the meaning given above, is

quaternised with a suitable quaternising agent. The process can be performed by simply heating a mixture of 4,4- bipyridyl (or the mono-quaternary salt as the case may be) with the quaternising agent. However, in some instances, especially where operating on a large scale, it may be more convenient to use a suitable liquid as solvent or diluent for the reactants. I

The invention includes herbicidal compositions containing as active ingredient a compound of the invention, and a carrier for the active ingredient. The composition can, for example, be a liquid composition obtained by dissolving or dispersing the active ingredient in a suitable diluent, for example water or a suitable organic liquid. The herbicidal composition alternatively can be in the form of a powder in which the active ingredient is in admixture with apowder diluent. The compositions can contain a wetttingor dispersing agent to facilitate their use as spray compositions, or indeed can contain any other type of substance known to the art as being, suitableas an adjuvantin herbicidal compositions; for instance stickers, binders, corrosion inhibitors and colouringjiagents.

Any wetting or dispersing agent usedin the herbicidal compositions should preferably be a non-ionic surfaceactive compound, for'instancevan ethylene oxide-octyl phenol condensate, 'or'a cationic compound, so-as to avoid any undesirable interaction between thesurface-active compound and the bipyridylium-salt which might take place if an anionic compound were'to be-tused as surfaceactive compound.

The invention further'consists in a method of killing, desiccating or otherwise severely damaging undesirable vegetation, in which the vegetation is treated with an effective amount of a. compound or herbicidal composition of this invention.

The invention is illustrated by the following examples.

EXAMPLE 1 N,N-di-isopropyl chloroacetamide (12.3 g.) and 4,4- bipyridyl (4.6 g.) were heated and stirred together at 100 C. until a homogenous liquid was obtained. The temperature of this liquid was then raised to 140 C. at which temperature a vigorous reaction took place and the mixture solidified. After heating the solidified mixture for 30 minutes, the solid was crushed, washed with acetone and recrystallised from about 300 ml. of ethanol, affording 1,1'-bis-(di-isopropylcarbamyl-methyl) 4,4'-bipyridylium dichloride. N0 melting point of the product has been recorded as the sample tested showed no sign of melting at temperatures up to 320 C.

EXAMPLES 2-16 and were obtained by a process in which there was used a chloroacetamide of the formulaz In each instance the chloracetamide and 4,4-bipyridyl were used in a molar ratio in the range 1:1 to 1.121.

The products of Examples 2-16 are identified in the table by the meaning given to the group and the melting point shown against the products are those obtained usinga. sample of the product which had been purified by recrystallisation, melting in each Patented 'May 1.7, 1966 The substances obtained as products of the examples have been testedfor-herbicidal activity against both broad-leafed plant species and grasses, and the results are expressed in the right-hand columns of the table.

compared with untreated control plants; it does. not

necessarily mean that 50% of the plants treated had Under the heading Herbicida'l activity is shownthe 5 been killed. The assessment of the herbicidal effect of amounts (in lbs/acre) of the various compounds, exthe substances tested was made as follows: pressed in terms of their respective cations, found neces- I Batches of plants of each of the broad-leafed and sary to obtain a 50% kill ofpthe species tested 14 days grass species were sprayed with aqueous solutions of after application to thetest plants. The broad-leafed the test substances at a range of concentrations. The and grass species (referred to in the table under the herbicidal damage caused to each batch was visually respective headings B and G) were as follows: assessed 14 days after spraying as a percentage, taking undamaged'control plants as 0% and completely dead Broad-leafed 1 plants as 100%. .The mean values obtained against all 8 beet f the broad-leafed species and the grass species at each f p 15 particular concentration was then calculated and these 1 Kale f olemcea) mean values were plotted against concentration on a Clove! (Tflfollum P logarithmic scale. From the resulting graph the con- Redshank (P y P centration of each substance required to produce 50% Mayweed (Matrzcana modora) kill was then read 11 The figures given in the extreme right-hand column Glass of the table under Index of Selectivity are the ratios WPeat (Tm'cum gare) of the adjacent figures against broad-leafed and grass Wlld oats (Avena fatfm) species and it will be seen that several of the compounds Barley (Hordeum ,smvum) show a most marked selective action against broad- Cocksfoot (Dactylzs glomerata) leafed species.

TABLE I Products 0! Examples Herblcldal activity Index of Example N0. R1 Sales Water 0! .P. tlvlty N crystallisation (de ctngp) B G Y -N o1rr11so Anhydrous--. 0.063 s 121 a013,--- 11,0 1 330 0.020 0.25 12 -N cH1)1.- Anhydrous--. 315 0.021 0.17 '8 N(C;H1n)1 2H0 277 0. 003 0.5, N(CH CH;-OC;Ht)1 244 0.067 28 420 N(CH,CH;OCH 258 0.030 0.s 215 N(CH1,-CN)1 320 0.17 5.0 30

10. -N H1O 205 0. 050 1.0 32

V 11 N/ 1r 0 302 0 050 s 0 102 '14 -N 2H,o... 208 0.077 s.0 104 N" 3H1O 282 0.3a 8 24 16.; ,N(CHzCHr-CN)2 Auhydrous .11 0.33 8 24 5 Patent No. 813,532 discloses 4,4'-dipyridyl di-(N,N- diethylcarbamylmethochloride), known also by the alternative name 1,1 bis-(diethylcarbamylmethyl)-4,4'-

' tests when applied as an aqueous solution to spores of wheat leaf rust (Puccinia recondita).

What we claim is:

1. A 4,4-bipyridy1iurn quaternary salt of the formula:

wherein R and R each represent the atoms necessary to complete,-together with the adjacent nitrogen atom, a heterocyclic radical selected from the group consisting of pyrrolidino, piperidino, morpholino, methyl-pyrrolidino, methyl-piperdino, methyl-morpholino and hexamethyleneimino; and X* in an anion.

2. A quaternary salt according to claim 1 wherein R and R each represent the atoms necessary to complete the 2-methyl piperino radical.

3. A quaternary salt according to claim 1 wherein R and R each represent the atoms necessary to complete the 3,5-dimethyl morpholino radical.

References Cited by the Examiner UNITED STATES PATENTS 2,769,818 11/ 1956 Schlessinger 712.5 2,913,323 11/ 1959 Cameron 712.5 2,914,392 11/1959 DAmico 712.5 2,929,818 3/ 1960 Janssen 260-295 2,972,528 2/ 1961 Brian 'et a1. 712.5 3,025,294 3/ 1962 Huebner 260.247 .5

FOREIGN PATENTS 813,532 5/1959 Great Britain.

NICHOLAS S. RIZZO, Primary Examiner.

IRVING MARCUS, Examiner. 

1. A 4,4''-BIPYRIDYLIUM QUATERNARY SALT OF THE FORMULA:
 3. A QUATERNARY SALT ACCORDING TO CALIM 1 WHEREIN R1 AND R2 EACH REPRESENT THE ATOMS NECESSARY TO COMPLETE THE 3,5-DIMETHYL MOROPHOLINO RADICAL. 